An X-ray tube is used as an X-ray source such as a medical X-ray device and a measuring device for industrial purposes. These X-ray tubes are classified broadly into rotating anode X-ray tubes and stationary anode X-ray tubes, and the previously mentioned transmission type X-ray tube belongs to the category of stationary anode X-ray tubes or to category of its own.
Recently, as disclosed in Patent Document 1, X-ray tubes have extended use application to an X-ray source in static eliminator.
Patent Document 1 relates to static eliminator and a method thereof for removing static electricity, and it removes static electricity on both sides of an object at the same time by radiating X-rays to the object.
In this manner, a removal of static electricity has become a significant issue in manufacturing or processing of products such as film or papers, filling of fine particles or liquid, and manufacturing or inspection process of devices such as semiconductor or display unit.
In Patent Document 2 a transmission type X-ray tube to use for static eliminator is described.
The transmission type X-ray tube described in Patent Document 2 is configured such that a ceramic stem unit held up with cathode pins and an X-ray window in which a target metal is deposited under the surface are supported by a ceramic bulb and bilaterally brazed, the focusing electrode is placed along the inner circumference of the ceramic bulb, and the lower end of the focusing electrode is held between the stem unit and the bulb.
Patent Document 1: JP-A-1995-6859
Patent Document 2: JP-A-1997-180660